Spherical annular seal member and method of manufacturing the same

Abstract

A spherical annular seal member which has a cylindrical inner surface defining a through hole in a central portion thereof, an outer surface formed in the shape of a partially convex spherical surface, and an annular end face on a large-diameter side of the outer surface, and which is used particularly in an exhaust pipe joint, comprises: a reinforcing member made from a compressed metal wire net; a heat-resistant material filling meshes of the metal wire net of the reinforcing member and compressed in such a manner as to be formed integrally with the reinforcing member in mixed form, the heat-resistant material and the reinforcing member being provided as principal components in an inner portion of the spherical annular seal member which extends from the cylindrical inner surface to the outer surface formed in the shape of the partially convex spherical surface, boron carbide, a metal boride, a metal fluoride, graphite, and aluminum phosphate being also formed integrally with the reinforcing member and the heat-resistant material in mixed form; an outer surface layer formed of boron carbide, a metal boride, a metal fluoride, graphite, and aluminum phosphate; and a reinforcing member made from a compressed metal wire net and formed integrally with the outer surface layer in mixed form, wherein the outer surface formed in the shape of the partially convex spherical surface is formed into a smooth surface where the outer surface layer and the reinforcing member made from the metal wire net and formed integrally with the outer surface layer in mixed form are exposed.

What is claimed is: 
     
       1. A spherical annular seal member which has a cylindrical inner surface defining a through hole in a central portion thereof, a partially convex spherical annular outer surface, and an annular end surface on a large-diameter side of the outer surface, comprising: an annular base portion including a matrix material comprising a first reinforcing member made from a compressed metal wire net and a compressed heat-resistant material filling meshes of said metal wire net, and a first composition mixed into said matrix material and comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate; and   an outer surface layer provided unitarily on said annular base portion and having said partially convex spherical annular outer surface, said outer surface layer including a second reinforcing member made from a further compressed metal wire net, and a second composition including at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate, said second composition being compressed and filling meshes of said further compressed metal wire net; said outer surface with said second reinforcing member and said second composition in mixed form with each other being smooth, whereby a heat resistibility of said annular base portion is improved and, during an operation of said spherical annular seal member, a solid lubricating coating is formed on a surface of a mating member which is mated to said spherical annular seal member.     
     
     
       2. A spherical annular seal member according to claim 1, wherein, said annular base portion includes 5 to 45 parts by weight of said first composition with respect to 100 parts by weight of said heat-resistant material. 
     
     
       3. A spherical annular seal member according to claim 1, wherein, said annular base portion includes said first composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, and said graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       4. A spherical annular seal member according to claim 1, wherein, said outer surface layer includes said second composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, and said graphite to said aluminum phosphate, and includes 5 to 25 of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       5. A spherical annular seal member according to claim 1, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate, respectively. 
     
     
       6. A spherical annular seal member according to claim 5, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, said graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       7. A spherical annular seal member according to claim 1, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       8. A spherical annular seal member according to claim 1, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       9. A spherical annular seal member according to claim 1, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       10. A spherical annular seal member according to claim 1, wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos. 
     
     
       11. A spherical annular seal member according to claim 1, wherein, said first composition and second composition further comprise a heat-resistant lubricant, respectively. 
     
     
       12. A spherical annular seal member according to claim 11, wherein, said annular base portion includes said first composition with 5 to 45 parts by weight of said at least one of boron carbide and metal boride, the metal fluoride, the graphite, the heat-resistant lubricant, and said aluminum phosphate with respect to 100 parts by weight of said heat-resistant material. 
     
     
       13. A spherical annular seal member according to claim 11, wherein, said annular base portion includes said first composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of the metal fluoride, 5 to 25 wt. % of the heat-resistant lubricant, and 50 to 80 wt. % of the graphite in that ratio. 
     
     
       14. A spherical annular seal member according to claim 11, wherein, said outer surface layer includes said second composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of said metal fluoride, 5 to 25 wt. % of said heat-resistant lubricant, and 50 to 80 wt. % of said graphite in that ratio. 
     
     
       15. A spherical annular seal member according to claim 11, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, a heat-resistant lubricant, and aluminum phosphate, respectively. 
     
     
       16. A spherical annular seal member according to claim 15, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of said metal fluoride, 5 to 25 wt. % of said heat-resistant lubricant, and 50 to 80 wt. % of said graphite in that ratio. 
     
     
       17. A spherical annular seal member according to claim 11, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       18. A spherical annular seal member according to claim 11, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       19. A spherical annular seal member according to claim 11, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       20. A spherical annular seal member according to claim 11, wherein said heat-resistant lubricant is of at least one kind selected from talc, mica, and boron nitride. 
     
     
       21. A spherical annular seal member according to claim 11, wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos. 
     
     
       22. A spherical annular seal member which has a cylindrical inner surface defining a through hole in a central portion thereof, a partially convex spherical annular outer surface, and an annular end surface on a large-diameter side of the outer surface, comprising: an annular base portion including a matrix material comprising a first reinforcing member made from a compressed metal wire net and a compressed heat-resistant material filling meshes of said metal wire net, and a composition mixed into said matrix material and comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate; and   an outer surface layer provided unitarily on said annular base portion and having said partially convex spherical annular outer surface, said outer surface layer including a second reinforcing member made from a further compressed metal wire net, and a lubricating composition including at least boron nitride and at least one of alumina and silica, said lubricating composition being compressed and filling meshes of said further compressed metal wire net; said outer surface with said second reinforcing member and said lubricating composition in mixed form with each other being smooth, whereby a heat resistibility of said annular base portion is improved.     
     
     
       23. A spherical annular seal member according to claim 22, wherein, said annular base portion includes 5 to 45 parts by weight of said composition with respect to 100 parts by weight of said heat-resistant material. 
     
     
       24. A spherical annular seal member according to claim 22, wherein, said annular base portion includes said first composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, and the graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and the metal boride, 1 to 15 wt. % of the metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       25. A spherical annular seal member according to claim 22, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate, respectively. 
     
     
       26. A spherical annular seal member according to claim 25, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, and the graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and metal boride, 1 to 15 wt. % of the metal fluoride, and 60 to 90 wt. % of the graphite. 
     
     
       27. A spherical annular seal member according to claim 22, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       28. A spherical annular seal member according to claim 22, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       29. A spherical annular seal member according to claim 22, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       30. A spherical annular seal member according to claim 22, wherein said lubricating composition includes 70 to 90 wt. % of said boron nitride and 10 to 30 wt. % of said at least one of alumina and silica. 
     
     
       31. A spherical annular seal member according to claim 22, wherein said lubricating composition further contains polytetrafluoroethylene resin. 
     
     
       32. A spherical annular seal member according to claim 31, wherein said lubricating composition contains 100 parts by weight of a mixture of 70 to 90 wt. % of said boron nitride and 10 to 30 wt. % of said at least one of alumina and silica, and further contains not more than 200 parts by weight of polytetrafluoroethylene resin. 
     
     
       33. A spherical annular seal member according to claim 22, wherein said lubricating composition contains 100 parts by weight of a mixture of 70 to 90 wt. % of said boron nitride and 10 to 30 wt. % of said at least one of alumina and silica, and further contains 50 to 150 parts by weight of polytetrafluoroethylene resin. 
     
     
       34. A spherical annular seal member according to claim 22 wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos. 
     
     
       35. A spherical annular seal member according to claim 22, wherein, said composition further includes a heat-resistant lubricant. 
     
     
       36. A spherical annular seal member according to claim 35, wherein, said annular base portion includes said composition with 5 to 45 parts by weight of said at least one of boron carbide and metal boride, the metal fluoride, the graphite, the heat-resistant lubricant, and said aluminum phosphate with respect to 100 parts by weight of said heat-resistant material. 
     
     
       37. A spherical annular seal member according to claim 35, wherein, said annular base portion includes said composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of the metal fluoride, 5 to 25 wt. % of the heat-resistant lubricant, and 50 to 80 wt. % of said graphite in that ratio. 
     
     
       38. A spherical annular seal member according to claim 37, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, heat-resistant lubricant, and aluminum phosphate. 
     
     
       39. A spherical annular seal member according to claim 38, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of the metal fluoride, 5 to 25 wt. % of the heat-resistant lubricant, and 50 to 80 wt. % of the graphite in that ratio. 
     
     
       40. A spherical annular seal member according to claim 35, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       41. A spherical annular seal member according to claim 35, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       42. A spherical annular seal member according to claim 35, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       43. A spherical annular seal member according to claim 35, wherein the heat-resistant lubricant is of at least one kind selected from talc, mica, and boron nitride. 
     
     
       44. A spherical annular seal member according to claim 35, wherein said lubricating composition includes 70 to 90 wt. % of said boron nitride and 10 to 30 wt. % of said at least one of alumina and silica. 
     
     
       45. A spherical annular seal member according to claim 35, wherein said lubricating composition further contains polytetrafluoroethylene resin. 
     
     
       46. A spherical annular seal member according to claim 35, wherein said lubricating composition contains 100 parts by weight of a mixture of 70 to 90 wt. % of said boron nitride and 10 to 30 wt. % of said at least one of alumina and silica, and further contains not more than 200 parts by weight of polytetrafluoroethylene resin. 
     
     
       47. A spherical annular seal member according to claim 35, wherein said lubricating composition contains 100 parts by weight of a mixture of 70 to 90 wt. % of boron nitride and 10 to 30 wt. % of at least one of alumina and silica, and further contains 50 to 150 parts by weight of polytetrafluoroethylene resin. 
     
     
       48. A spherical annular seal member according to claim 35, wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos. 
     
     
       49. A seal assembly comprising: a spherical annular seal member which has a cylindrical inner surface defining a through hole in a central portion thereof, a partially convex spherical annular outer surface, and an annular end surface on a large-diameter side of the outer surface;   a mating member having a partially concave spherical annular surface for mating engagement with said partially convex outer surface of said seal member; said annular member having an annular base portion including a matrix material comprising a first reinforcing member made from a compressed metal wire net and a compressed heat-resistant material filling meshes of said metal wire net, and a first composition mixed into said matrix material and comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate; and     an outer surface layer provided unitarily on said annular base portion and having said partially convex spherical annular outer surface, said outer surface layer including a second reinforcing member made from a further compressed metal wire net, and a second composition including at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate, said second composition being compressed and filling meshes of said further compressed metal wire net; said outer surface with said second reinforcing member and said second composition in mixed form with each other being smooth, whereby a heat resistibility of said annular base portion is improved and, during an operation of said seal assembly, a solid lubricating coating is formed between said partially concave surface of said mating member and said partially convex surface of said spherical annular seal member.     
     
     
       50. A seal assembly according to claim 49, wherein, said annular base portion includes 5 to 45 parts by weight of said first composition with respect to 100 parts by weight of said heat-resistant material. 
     
     
       51. A seal assembly according to claim 49, wherein, said annular base portion includes said first composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, and said graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       52. A seal assembly according to claim 49, wherein, said outer surface layer includes said second composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, and said graphite to said aluminum phosphate, and includes 5 to 25 of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       53. A seal assembly according to claim 49, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, and aluminum phosphate, respectively. 
     
     
       54. A seal assembly according to claim 49, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, said metal fluoride, said graphite to said aluminum phosphate, and includes 5 to 25 wt. % of said at least one of boron carbide and metal boride, 1 to 15 wt. % of said metal fluoride, and 60 to 90 wt. % of said graphite in that ratio. 
     
     
       55. A seal assembly according to claim 49, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       56. A seal assembly according to claim 49, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       57. A seal assembly according to claim 49, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       58. A seal assembly according to claim 49, wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos. 
     
     
       59. A seal assembly according to claim 49, wherein, said first composition and second composition further comprise a heat-resistant lubricant, respectively. 
     
     
       60. A seal assembly according to claim 49, wherein, said annular base portion includes said first composition with 5 to 45 parts by weight of said at least one of boron carbide and metal boride, the metal fluoride, the graphite, the heat-resistant lubricant, and said aluminum phosphate with respect to 100 parts by weight of said heat-resistant material. 
     
     
       61. A seal assembly according to claim 49, wherein, said annular base portion includes said first composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of the metal fluoride, 5 to 25 wt. % of the heat-resistant lubricant, and 50 to 80 wt. % of the graphite in that ratio. 
     
     
       62. A seal assembly according to claim 49, wherein, said outer surface layer includes said second composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal bonds, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of said metal fluoride, 5 to 25 wt. % of said heat-resistant lubricant, and 50 to 80 wt. % of said graphite in that ratio. 
     
     
       63. A seal assembly according to claim 49, wherein further comprises a first heat-resistant layer provided unitarily on said annular base portion and having said cylindrical inner surface, and a second heat-resistant layer provided unitarily on said annular base portion and having said annular end surface, each of said first and second heat-resistant layers including a further composition comprising at least one of boron carbide and metal boride, metal fluoride, graphite, a heat-resistant lubricant, and aluminum phosphate, respectively. 
     
     
       64. A seal assembly according to claim 49, wherein, each of said first and second heat-resistant layers includes said further composition with 1:0.5 to 3 in a weight ratio of said at least one of boron carbide and metal boride, the metal fluoride, the heat-resistant lubricant, and the graphite to said aluminum phosphate, and includes 5 to 20 wt. % of said at least one of boron carbide and metal boride, 3 to 15 wt. % of said metal fluoride, 5 to 25 wt. % of said heat-resistant lubricant, and 50 to 80 wt. % of said graphite in that ratio. 
     
     
       65. A seal assembly according to claim 49, wherein the metal boride is selected from among Groups IVa, Va, and VIa of a periodic table of elements. 
     
     
       66. A seal assembly according to claim 49, wherein the metal boride is selected from among titanium boride, titanium diboride, zirconium diboride, zirconium dodecaboride, halfnium diboride, vanadium diboride, niobium diboride, tantalum diboride, chromium boride, chromium diboride, molybdenum boride, molybdenum diboride, dimolybdenum boride, dimolybdenum pentaboride, tungsten boride, tungsten diboride, ditungsten boride, and ditungsten pentaboride. 
     
     
       67. A seal assembly according to claim 49, wherein the metal fluoride is of at least one kind selected from calcium fluoride, lithium fluoride, sodium fluoride, and barium fluoride. 
     
     
       68. A seal assembly according to claim 49, wherein said heat-resistant lubricant is of at least one kind selected from talc, mica, and boron nitride. 
     
     
       69. A seal assembly according to claim 49, wherein said heat-resistant material is of at least one kind selected from expanded graphite, mica, and asbestos.